The black post is for ground, the red posts are for voltage supplies.
The positive "end" of the battery is connected red post 1.
All grounds are connected to the black post.
All positive 9V are connected to red post 1.
The negative "end" of the battery is connected to the black post.
The positive "end" of the battery is connected red post 1.
All grounds are connected to the black post.
All positive 9V are connected to red post 1.
The negative "end" of the battery is connected to the black post.
